Why are some URLs in the Canonical section blue while others are red?

When you use Site Crawl to analyze your website, it will include every canonical URL it finds while crawling your pages. The crawler does this because it can only see whether or not a canonical tag is implemented correctly from a technical standpoint. We can’t see if your canonical tag points to the right URL. You still need to know where your canonical tags point just in case.

To help guide you, Site Crawl color codes its canonical results according to what we know about them:

Blue: These are listed just for informational purposes. You should still verify they’re pointing to the right URL, but they likely aren’t impacting your SEO.

Orange: These are medium priority issues. Fixing them will improve your SEO, but won’t have as much of an impact as the red errors.

Red: These are high priority, critical issues that are having a high impact on your SEO. These errors should be fixed immediately.